gemstone

Diamond

C (Carbon)

Hardness: 10 (Mohs scale), Color: Colorless to faint yellow/brown, Luster: Adamantine, Crystal Structure: Cubic, Cleavage: Perfect octahedral, Specific Gravity: 3.52

Identified July 10, 2026More gemstone →

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Physical properties

Hardness: 10 (Mohs scale), Color: Colorless to faint yellow/brown, Luster: Adamantine, Crystal Structure: Cubic, Cleavage: Perfect octahedral, Specific Gravity: 3.52

Formation & geological history

Formed under high-pressure, high-temperature conditions deep in the Earth's mantle, approximately 100 miles underground. They are brought to the surface by explosive volcanic eruptions called kimberlite or lamproite pipes. Most diamonds are between 1 to 3 billion years old.

Uses & applications

Primarily used in high-end jewelry (engagement rings, necklaces) and for industrial purposes such as cutting, grinding, and drilling due to its extreme hardness.

Geological facts

Diamond is the hardest natural substance known to man. The word diamond comes from the Greek word 'adamas', meaning unbreakable or invincible. While most people think of colorless diamonds, they can occur in almost any color including blue, green, and pink.

Field identification & locations

In the field, it is often found in kimberlite pipes or alluvial deposits (riverbeds). Identification requires professional gemological tools as it is easily confused with Cubic Zirconia or Moissanite. Look for high luster, sharp facet edges, and its ability to scratch any other mineral.